Balanced conveyor hopper



3, 1965 R. MIGHELL Re. 25,832

BALANCED CONVEYOR HOPPER Original Filed May 1, 1961 7 Sheets-Sheet 1INVENTOR: fiiJSSEZZ L. Mzghell Aug. 3, 1965 R L. MIGHELL BALANCEDCONVEYOR HOPPER '7 Sheets-Sheet 2 Original Filed May 1. 1961 Aug. 1965R. L. MIGHELL Re. 25,832

BALANCED CONVEYOR HOPPER Original Filed May 1. 1961 '7 Sheets-Sheet 3 28INVENTOR.

/ 56 Russell L. Might? [l 1965 R. MIGHELL Re. 25,832

BALANCED CONVEYOR HOPPER Original Filed May 1. 1961 '7 Sheets-Sheet 4INVENTOR: Q

) 314455661 11. Mfg/L655 Aug. 3, 1965 R. MIGHELL BALANCED common norm;

7 Sheets-Sheet 5 Origlnal Filed May 1, 1961 INYEN TOR: fza 356/! L. M

gg/zsll Aug. 3, 1965 R. L. MIGHELL BALANCED CONVEYOR HOPPER 7Sheets-Sheet 6 Original Filed May 1, 1961 l m 6 wk 1 1403665! L. Ml:

Aug. 3, 1965 M|GHELL Re. 25,832

BALANCED CONVEYOR HOPPER Original Filed May 1. 1961 '7 Sheets-Sheet '7H@ 06f (H/i916 m Dggrees Jfo er from 8,1 fmm I [re/ 5 2a,! io 0er'czi'igg INVENTOR: jiassell L. [Wig/i611 BY may I United States PatentOflice Re. 25,832 Reissued Aug. 3, 1965 25,832 BALANCED CUNVEYOR HQPPERRussell L. Mighell, Kewanee, Ili., assignor to Kewanee Machinery &Conveyor Company, Kewanee, lll., a

corporation of Illinois Original No. 3,059,754, dated Oct. 23, 1962,Ser. No.

106,741, May 1, N61. Application for reissue Sept.

14, 1964, Ser. No. 410,337

25 Claims. (Cl. Bil-93) Matter enclosed in heavy brackets appears in theoriginal patent but forms no part of this reissue specification; matterprinted in italics indicates the additions made by reissue.

This invention relates to a material conveyor adapted for movingmaterials between different levels and to a conveyor provided with aswingable hopper at its receiving end for material acceptance anddelivery to the elevator portion of the conveyor.

More specifically, this invention is directed to a farm type conveyorhaving a tilting hopper to receive material being conveyed and to passsuch material onto the conveyor, such hopper being controlled by acounterbalancing mechanism arranged to reduce manual effort to a minimumfor an operator while moving such hopper into its various adjustedposition relative to the conveyor.

Tilting hoppers of conventional designs are usually provided onconveyors to be moved between a horizontal operating position to asuitable vertical non-operating position by displacement over an arc ofabout 107 as an average consideration. Some hoppers are held in suchupright relations to the conveyor while others may be made to assumesome overcentcr positions beyond the 107 arc to occupy non-operativestored positions or travel position.

It has been determined that the effort which is required to balance atilting hopper at any point along its arc of movement is proportional tothe sine of the angle to which the hopper is raised. Hence this effortresolved into a force may be plotted as a curve from zero force when thehopper is in vertical balance position to the full load force thereofwhen the hopper is near to its horizontal operating position.

Hoppers of the tilting kind are rigged with coil springs for balancingefforts to overcome some of the dead weight during angular manipulation.A coil spring characteristically has a uniform force rate from zeroextension to maximum extension under full load. Hence the plotting ofthe spring force will develop a straight line graph which does notfollow the load force of the hopper as it is raised or lowered.

When an attempt is made to balance a hopper by attaching hopperbalancing springs to fixed points on the conveyor, they fail to achieveperfect balance due to their straight line characteristics. However, dueto the restraint of the fixed pivot at the head of the hopper, the forcecurve does curve slightly, but it still will only balance the hopper atone or two points, depending on'the location of the fixed attachingpoints on the conveyor for the springs. On the other hand, if theattaching points of the springs on the conveyor could be moved to theirmost advantageous positions for each degree or few degrees of rise asthe hopper is raised, the hopper could be made to be held in balance atany point along its arc of manipulation.

It is an object of this invention to provide a hopper balancingmechanism including a linkage means wherein the spring attachmentpoints, which are duplicated on each side of the conveyor, areautomatically shifted or moved during the raising of the hopper so thatthe resultant lifting forces of the springs vary so as to approximatethe plotted curve of the force that is required to balance the hopper asit is raised from ground position to a vertical position or vice versa.

As previously noted above, the hopper is pivoted on the forward groundcontacting end of the material ele vating conveyor and the hopper, forexample, swings through an arc of about 107 from an upright or verticalbalance position to a horizontal ground engaging operative positionahead of the conveyor.

The linkage means of the present invention is designed to provideleverage so that the springs will achieve a balance condition on thehopper through the upper portion of the are (for about 80), and then asthe hopper approaches the lowered horizontal operating position, theleverage of the attaching points changes gradually through the last 27so that the hopper will lastly stay down in its operating position asregulated by a portion of its own weight.

It is, therefore, another object of the invention to provide acounterbalancing means for a tilting hopper of a conveyor whereinshiftable or variable means is used to change the balancing springleverage as the hopper describes a greater portion of its arc of traveland wherein the last portion of hopper travel is controlled by a springforce leverage in a manner to develop some excess force by reason of anapportionment of the weight of the hopper in a position to hold thelatter on the ground and in operative relation to the conveyor.

As hereinbefore mentioned, the hoppers of conveyors of the kindgenerally discussed are normally stored in a vertical or uprightnon-operating position over the ground end of the elevator of theconveyor. It is, however, desirable and advantageous to be able to bringthe hopper to rest somewhat over center toward the elevator portion ofthe conveyor which will place the hopper in a more convenient positionof access for an operator when he is ready to swing the hopper into thedown and operating position.

It is a further object to provide a spring connected link means thatwill function in a manner to allow the hopper to pass through a low loadphase vertical position toward a position of rest wherein the link meansact to increase the spring leverage after the hopper moves over centerand which link means is capable of bringing the hopper to a stopgradually and gently without shock as the springs absorb the load energyof the hopper movement at a given angular relation above the run of theconveyor.

Conveyors of this kind are adjustable to different angular positions tochange the inclination of the elevator in relation to the ground toplace the discharge end of the conveyor at a selected elevation. Thiscauses a limited angular inclination range of operation for the conveyorwhich will change the angular position of the conveyor in relation tothe surface of the ground. This change of conveyor angularity alsocauses the hopper to swing through an arc of operation that varies inrelation to a vertical reference plane intersecting the pivotal axis ofthe hopper.

As a further object, therefore, the hopper balancing mechanism has beenconstructed to include an adjustable regulation so as to beneficiallyaccommodate itself to each condition of hopper swing for the variousangular conveyor positions of the elevator in serving differentdischarge elevations. This regulation and adjustment is incorporatedinto the link means employed and includes a range of variations thatwill adjust for the change in the position of the elevator betweenapproximately 17 to 45 the normal range conventionally acceptable formost conditions of operation.

Other objects and advantages relating to the balanced conveyor hopper ofthe present design and invention shall hereinafter appear in or becomeapparent from the following detailed description having reference to theaccompanying drawings which form a part of this specification.

In the drawings:

FIG. 1 is a diagrammatic perspective view of a farm conveyorincorporating the newly devised mechanisms of the present invention thatserve to balance the hopper structure of the conveying elevator;

FIG. 2 is a fragmentary side elevational view of the left side (viewedfrom the hopper end) of the ground end of the conveyor with the hopperoccupying its lowered position for operatively receiving materials forfeeding the elevator section of the conveyor;

FIG. 3 is a transverse vertical cross sectional view taken through theconveyor structure substantially along the plane of the line 33 in FIG.2;

FIG. 4 is another transverse vertical cross sectional view taken throughthe hopper section of the conveyor and substantially along the plane ofthe line 44 in FIG. 2;

FIG. 5 is an enlarged side elevational view of a fragmentary portion ofthe left side of the conveyor to better illustrate some of the detailsof the mechanisms of this invention;

FIG. 6 is a fragmentary detail view partially in section to show somedetails of the link means of the mechanism that balances the hopper;

FIG. 7 is a perspective view of the left side portion of the ground endof the conveyor and its attached hopper;

FIG. 8 is another perspective view of the same general portion of thehopper end of the conveyor, but as viewed from the right hand sidethereof;

FIG. 9 is an enlarged fragmentary vertical cross sectional view of thepivotal arrangement at one side of the hopper and conveyor that showstructural details of the right hand portion of FIG. 3;

FIG. 10 is a detailed face view of the bearing means as the same appearswhen viewed substantially along the plane of the line 1010 in FIG. 9;

FIG. 11 is a graph diagrammatically showing certain of the relationshipsdescribed and to be further explained in support of the efficiency andbeneficial operation of the hopper balancing mechanism herein disclosed.

The exemplary conveyor 1 best shown in FIG. 1 comprises an elevatorportion 2, delivery spout 3, material receiving hopper 4 and suitableconveyor elevating mechanism such as the crank means 5 with cables 6 allconnected to raise and lower the elevator portion 2 on the wheeledsupporting frame 7 provided for adjusting and changing the angularelevation of the conveyor with respect to the ground.

As best illustrated in FIGS. 2, 7 and 8, the front or lower ground endof the conveyor shown at 8 rests on the ground on the hitch rods 9 thatcarry the towing bracket 10 which is used to haul the conveyor when thehopper 4 is swung over the elevator portion 2 in a nonuse position.

The elevating or conveying mechanisms comprise suitable chain driveslocated in the conveyor chute and in the hopper, the two chain driveshaving a common external power drive and connected chain drives tosynchronize the material advance in the chutes. The external drive maybe had from a suitable power source such as a tractor, engine, or thelike. In FIG. 7, a drive shaft 11 connects with a suitable sprocketshaft 12 that transmits the drive by suitable sprocket and chain to asprocket 13 secured to the main forward or lower drive shaft 14 of theconveyor. Shaft 14 carries suitable sprockets 15 and 16 to actuatespaced chains 17 and 18 supplied with connecting slats 19 that providethe material elevating flight structure of the conveyor, traveling overa suitable upper sprocket carrying shaft 20.

As shown in FIG. 8, shaft 14 is equipped with a sprocket 21 on theconveyor on the right side (looking at the conveyor from the hopper end)to drive a connecting chain 22 that is trained over a sprocket 23secured to the hopper drive shaft 24. Spaced chain drive sprockets 25and 25a are secured to shaft 24 as seen in FIG. 3, and such sprocketspropel chains 26 and 27 that carry slats 28 crosswise of the hopper forlongitudinal movement through the hopper chute to feed the conveyorchain flight. As will be further described, the shaft 24, whileproviding an essential part of the conveying system, this same shaft 24also furnishes the pivotal support of the conveyor attached end of thehopper 4 which is best evident from inspection of FIGS. 2, 3 and 9.

The hopper support and pivotal structure best appearing in FIGS. 2, 3,5, 7, 8 and 9, comprises a pair of side plates 29 and 30 that areprovided with base angles 31 and 32 that seat and are attached to thereinforced top rails 33 and 34 of the conveyor sides 35 and 36.

The hopper sides 37 and 38 each have holes 39 and 40 coaxiallypositioned with respect to shaft 24 and flanged bearings 41 and 42 aresecured to the sides 37 and 38, the bearings being provided with centralopenings 43 and 44 that also coaxially surround shaft 24 as bestillustrated in FIGS. 3 and 9. Ball bearing units such as 45 are securelyoriented and mounted between the bearings 41 and 42 and the adjacenthopper sides 37 and 38 in the manner shown in FIGS. 3 and 9.

The mounting side plates 29 and 30 are each provided with apertures 46and 47 located coaxially with shaft 24 and have annular bearing flanges48 and 49 that rotatively receive the shouldered bearing bosses 50 and51 formed upon the flanged bearings 41 and 42.

The flanged bearings 41 and 42 are provided with radially positionedvertical faces 52 and 53 to ride against the edges of the bearingflanges 48 and 49 for lateral stability of the hopper pivotal and drivesystem described. These bearing assemblies are each further augmented bycup shaped retention washers 54 and 55 that are secured to the bearingbosses 50 and 51 by bolts such as 56 that also serve to secure the ballbearing units 45 and the flanged bearings 41 and 42 to the hopper sides37 and 38.

The hopper chains 26 and 27 have their two flights (as seen in FIG. 4)running over the upper auxiliary cross floor 57 for advancing materialand returning therebelow over the lower floor 58 spanning the spacebetween the hopper sides 37 and 38, the elevation of the hopper chaindrive discharge end being above the elevation of the conveyor receivingchain drive location at the ground end of the conveyor to drop materialonto the conveyor chain flight.

From the foregoing description, it will be understood that the hopper asa unit can be bodily swung about shaft 24 on the two bearing assembliesdefined, which will provide a structure that will allow an operator tomove the hopper between suitable stored and operative positions. Thestored position is normally upright or over the conveyor which is alsothe transport position, while the operative material receiving positionof the hopper is down upon the ground ahead of the conveyor and in agenerally horizontal relation.

Obviously with a hopper which, for example, weighs 215 pounds spread outover the long length of the hopper, it is difficult to raise this unitand also hard to handle when reversing this operation. The inventionherein disclosed is directed to a counterbalancing arrangement for thehopper that will permit an operator to swing the hopper quite freely andwith a minimum of physical effort. The counterbalancing means isduplicated at each side of the conveyor-hopper union location andgenerally, except for the individual connections with shaft 24, thecounterbalancing means are each solely carried on the sides of thehopper and made operational from these locations.

One side arrangement of the counterbalancing mechanism will be describedby reference numbers that will be duplicated but primed at the otherside of the hopper,

thus indicating like parts in a simple but differentiating manner onopposite sides of the conveyor.

As best illustrated in FIGS. 2, 3 and 5, a counterbalancing link means57 comprises a pair of toggle links 58 and 59 pivotally joined by a pin60, with link 58 riding on a crank or pivot pin as a stub shaft 61welded or otherwise fastened to the rim portion of the left retentionwasher 54. The second link 59 has a pivot pin 62 that is lodged into andheld in one of the spaced openings 63 formed in the side plate 29 on theconevyor. An intermediate guide bar 64 is secured to the face of theside plate 29 to provide an elongated slot 65 for the link 58 tostabilize the latter adjacent the face portion of plate 29 thus keepingthe link parts in their plane of operation at all times during themanipulation of the hopper about its pivotal supporting shaft 24.

The link 58, which may also be referred to as a spring arm, carries ashort spring link 66 on a pin 67, the link 66 having an aperture 68 toaccept the hook end 69 of the counterbalancing spring 70. Spring 70flanks hopper side 37, and as seen in FIG. 2 is provided with a secondbook end 71 to hook into the aperture of an eyebolt 72 that is securedto an anchor shaft or tube 73 held in the hopper proper.

The upper end of the link or spring arm 58 is made with tapered edges at74 and 7 5 to provide a symmetrical link for use on either side of theconveyor or with either face toward the hopper. However, as shown, onetapered edge 75 does function in a definite manner in coaction with link66. FIG. 6 shows link 66 in section with legs 76 and 77 made to straddlespring arm 58, the link 66 having a dual tapered connecting head 66a toprovide surfaces 78 and 79, only one of which is actively functional,the other being for symmetry. When the hopper 4 is swung upwardly to apredetermined vertical position, the surface 79 engages the tapered edge75 of link 58 and both the links will then act as a single link underthe action of spring 70 which now acts in a direction to hold the stopsurfaces together when the hopper is beyond the predetermined verticalpoistion above the conveyor. This selected position is approximatelycoincident with the position B of the hopper as illustrated in brokenlines in FIG. 2 of the drawings.

The link means 57 is made adjustable in operation to accommodate themost efiicient performance of counterbalancing in relation to the angleof inclination of the elevator 2 of the conveyor 1. This regulation oradjustment is made possible by shifting pin 62 into different ones ofthe holes 63 on the side plate 29 shown in FIG. 5. Obviously, both pins62 and 62' are shifted for each particular setting.

To determine the proper and correct positions of pins 62 and 62' inrelation to the elevator inclination, an indicator is provided in theform of a free hanging pointer 80 pivotally suspended from a pin 81secured to the face of the side plate 29 as best seen in FIG. 5. Thepointer acts as a plumb hob and indicia is provided at 82 in the form ofgraduations from 1 to 6 for elevator inclinations between 17 and 45, thesetting of the pointer establishing which of the holes 63, also markedcorrespondingly from 1 to 6, is to be used for reception of the pin 62to hold the end of link 59 in the appropriate pivotal relation on plate29. Pin 62' is placed in the aligned hole 63' on plate 30, the latterbeing marked 1 to 6 for the corresponding holes.

As stated in the objects, the link means and spring arrangement aredevised to aid in the swinging of the hopper from the ground to a storedposition and vice versa. The link means is controlled in operation bybeing directly responsive to the turning of the bearing assemblies whichfollow the angular motion of the hopper as it rotates about the axis ofshaft 24. The effective moment of pull of the springs is varied inrelation to the pivotal axis of the hopper by a displacement of thepoints of attachment of the springs at the pivotally supported end ofthe 63 hopper, the springs remaining attached to the hopper sides atfixed locations in their outboard positions relative to the pivotal axisof said hopper.

The moments of the spring system are varied automatically to compensatefor the changing torque of the hopper as it assumes differentangularities between a normal vertical no torque position and itsoperative ground engaging position. FIG. 11 demonstrates the variousvalues of hopper torque in inch pounds plotted against the hopper anglein degrees. The zero line is vertically shown and represents the notorque position of the hopper wherein its center of gravity is disposedvertically over its pivotal axis coincident with the axis of shaft 24,in which position springs 70 and 70' are actually fully retracted andloosely constituted between their hook ends 69 and 71, although notloose enough to cause displacement. This zero position is depicted bythe broken line position A shown in FIG. 2 of the drawings.

The above relationship is indicated by the legends in FIG. 11, the rightportion of the graph covering the action of counterbalancing of thehopper from zero upright position A to the ground touching positionshown in full lines in FIG. 2. The left portion of the graph shows theover center action of the hopper to a position of storage, which isposition B in FIG. 2 with link 59 having pin 62 in the top hole 63.Position B, at noted in the graph, is established under the locked linkcondition, links 58 and 66 being as shown in broken lines in FIG. 6, andthe balanced stop position of the hopper coming about by a balance ofthe moment of the springs and the hopper, the moments becoming equal atthe point indicated on the graph.

By moving link 59 with its pin 62 in hole number 6 on plate 29, thehopper can be brought into a transportable position as illustrated inbroken lines at C in FIG 2, thus reducing the overall height of theconveyor at its head end while traveling. This shift of pin 62 holds thehopper in balance in the relation shown.

In the graph, the broken dotted line is shown to demonstrate what takesplace in structures where the springs connect with fixed points on thehopper end and with fixed points on the conveyor structure. In contrast,the dot and dash line on the graph illustrates how the linkage means ofthe present invention develops variable moments that substantiallyfollow the full line moment action of the hopper per se.

The deviation between the dot and dash line and the hopper moment lineat the top of the graph at the right is used to advantage in providingthe hopper with some excess torque value to help in keeping the hopperagainst the ground in operative loading position which is desirable. inFIG. 2, the pull of spring 70 is from a position below line a--b at theouter end of the hopper to a position above the line a-b at the pivotalend of the hopper. with line a-b being drawn through the pivotal axis ofshaft 24 and the center of gravity of the hopper. This is therelationship shown at the upper right hand side of the graph in F16. 11.

And as previously mentioned, the links 58 and 66 are provided with thelocking members to develop a longer rigid link for over center leverageto enact with the spring action to cause quicker hopper load retainingcharacteristics to store the hopper in position B just beyond the notorque vertical dead center position shown at A, as seen in FIG. 2.

Thus the invention provides a variable linkage controlled spring momentcondition that forcewise simulates but counteracts the moment of thehopper about a fixed pivotal mounting on the conveyor providing asimple, feasible and efficient counterbalancing arrangement. In effect,the linkage means responsive to and controlled by hopper movement,actually establishes hopper weightlessness under its operation betweenits various maximum positions, ranging from stored to operativepositions. The hopper in the constructions illustrated weighs about '2'215 pounds and its full length is about 10 to 11 feet from the pivotalshaft 24 to the outer terminal ground end thereof.

The changeable leverage of the linkage spring arm 58 may be bestobserved in FIG. 2 wherein the full line position of this link to thespring 70 attaching point is at a minimum, while the spring expansion isat its maximum. The cup washer 54 on the hopper is turned to itsgreatest clockwise position bringing the pin 61 into the loweredposition shown in FIGS. 2 and 5. As the hopper is raised, cup washer 54rotates in a counterclockwise manner to extend the effective leverage oflink 58 to gradually cause pin 67 to move with its spring link 66further away from the axis of shaft 24 and the spring 70 begins toretract in length under the automatic change in the point of attachmentof such spring with the linkage considered with respect to the axis ofshaft 24 which remains unchanged.

When the hopper passes through position A in FIG. 2, the links 58 and 66become locked with the contact of surface 79 with edge 75 and the spring70 now acts on the outer end of the combined link 58 and 66 to create amoment of retarding force of a value to let the hopper come to rest inthe position B in FIG. 2. The same action unfolds itself under reverseconditions to hold the hopper in balance on its way to the ground.

The foregoing description has been directed to one specific embodimentof the invention illustrated in the drawings. However, certain changesin the exact design of the elements shown or in the exact combinationspresented are contemplated and the figures given by way of example mayalso be varied without departure from the fundamental concept of thisinvention. The contemplated modifications shall, therefore, bepermissible in latitude to the extent of the breadth and scope of thelanguage expressed in the hereinafter claimed subject matter directed tothe balanced conveyor hopper of this invention.

What I claim is:

1. In a conveyor, an elevator unit, a hopper unit, pivotal means tosupport said hopper unit for swinging movement relative to said elevatorunit about one axis, and counterbalancing means to hold said hopper unitin balance during the raising and lowering thereof about said pivotalmeans comprising a link mechanism swingably connected with one of saidunits and having operative swingable connection with said pivotal meanson another axis offset with respect to said one axis, spring meansconnected with said hopper unit and with a given part of said linkmechanism, said hopper unit being connected to cause rotation of saidpivotal means during the swinging movement of the hopper unit, said linkmechanism providing apparatus to actuate said part thereof in apredetermined relation with respect to the axis of the pivotal means toautomatically vary the effective pull of said spring mean through thelink mechanism to keep said hopper unit in balance during the differentangular positions assumed thereby during its swing.

2. A counterbalancing apparatus for a tilting hopper on a conveyorcomprising, in combination, a hopper chute, a conveyor chute, pivotalmeans connecting said chutes to permit said hopper chute to swing bodilybetween operative and inoperative positions in relation to said conveyorchute about a given axis, a link mechanism on said conveyor chute, and aspring connected between said hopper chute and said link mechanism toprovide the counterbalancing action for said hopper chute, said linkmechanism having an operative fulcrumed connection with said hopperchute upon an axis radially spaced from said given hopper chute axis ofrotation of said hopper chute upon said conveyor chute, whereby saidlink mechanism is actuated in response to the tilting motion of saidhopper chute, said link mechanism being constructed and arranged toregulate the effective line of pull of th spring in relation to thehopper chute axis on the conveyor chute to balance the hopper chute asit assumcs different angular positions with respect to the conveyorchute.

3. In combination, in a conveyor, an elevator, a hopper for saidelevator, pivotal means on said elevator supporting said hopper andhaving a rotatable element connected with said hopper to follow themotion thereof while tilting between operative and inoperative positionsabout said pivotal means, and counterbalancing mechanism for said hoppercomprising an articulate linkage having one end pivotally mounted onsaid elevator and its other end pivotally connected with said rotatableelement of said pivotal means, and spring means connected between atleast one of the members of said linkage and an outboard portion of saidhopper, tilting of said hopper providing rotary actuation of saidrotatable element of said pivotal means to operate the articulatelinkage to automatically cause the linkage to change the effective lineof pull of said spring means in relation to the axis of swing of saidhopper in a manner to keep said hopper in balance with said springmeans.

4. In combination, in a conveyor, an elevator, a hopper for saidelevator, pivotal means on said elevator to support said hopper fortilting between operative and inoperative positions, andcounterbalancing mechanism for said hopper comprising an articulatelinkage having one end pivotally mounted on said elevator and its otherend connected with said pivotal means, and spring means connectedbetween at least one of the members of said linkage and an outboardportion of said hopper, tilting of said hopper providing rotaryactuation of said pivotal means to operate the articulate linkage toautomatically cause the linkage to change the effective line of pull ofsaid spring means in relation to the axis of swing of said hopper in amanner to keep said hopper in balance with Said spring means, saidelevator including means to adjust the inclination of said elevator inrelation to the ground, such adjustment acting to change the limits ofthe angular swing of said hopper in relation to the elevator, saidelevator being provided with multiple attachment means to selectivelyreceive said one end of the articulate linkage in different positions,said attachment means establishing a range of connections that eachserve to adjust the operation of said linkage for counterbalancing thehopper in accordance with the particular inclination of said elevator.

5. In the combination of claim 4, with the addition of cooperative plumbbob mechanism on said elevator having indicia means to indicate to whichof said attachment means said one end of the articulate linkage shouldconnect to serve the hopper for the particular inclination occupied bysaid elevator.

6. A conveyor comprising an elevator, a hopper to supply material tosaid elevator, a fulcrum shaft on said elevator to pivotally support thehopper thereon for tilting from an inoperative position above saidelevator to an operative ground engaging position beyond the ground endof said elevator, and countcrbalancing mechanism to keep said hopper inbalance while moving between the positions noted, said mechanismcomprising a pair of pivotally joined links, a bearing unit connectedwith said hopper and rockably disposed in relation to said fulcrumshaft, said links being pivotally connected with a fixed portion of saidelevator and with said rockable bearing unit, and spring means havingone end attached with the joined links intermediate their connectionswith said elevator and the bearing unit, the other end of aid springmeans being connected with the hopper, rotation of said bearing unit bysaid hopper about said fulcrum shaft causing said joined links to changethe effective line of pull of the connected spring means in relation tothe fulcrum shaft to compensate for the torque load changes inproportion to the angular hopper positions when said hopper ismanipulated between operative and inoperative positions.

7. In a conveyor as in claim 6, wherein a separate spring arm isinterposed between the spring means and the pivotally joined links andpivoted on one of said links, and cooperative lock means are provided onsaid spring arm and on said one link, said cooperative lock means beingautomatically rendered effective by the spring means as the hopperreaches a predetermined upright position, continued motion of saidhopper beyond said position being arrested by the leverage of saidlocked link and arm on said spring means.

8. In a conveyor as in claim 7, wherein at least one of the joined linksand said elevator include adjustable securing mechanism disposed remotefrom the juncture of said link with its companion link whereby to changethe final angle of arrest of the hopper in relation to the elevator.

9. In a conveyor having an elevator and a swingable hopper at its groundend, a counterbalancing mechanism to balance the hopper comprising ashaft to pivotally support the hopper on said elevator, crank meanssecured to said shaft, link means on said elevator having connectionwith said crank means, and spring means connected with said link meansand with a remote point on said hopper, said link means establishing alever structure to coact with the spring means to develop a moment offorce to oppose the torque force of the hopper about said shaft, saidhopper having connection with said crank means to rotate the same duringhopper motion, and said link means functioning to vary the leveragethereof in conjunction with said spring means in a predeterminedproportion to the opposing torque force of the hopper while the latteris being angularly swung about its supporting shaft.

10. In a conveyor combination as in claim 9, wherein said link meansincludes a pivotal connection joined with said elevator at a selectedlocation to cause said spring means to balance said hopper over onerange of bodily swing, said pivotal connection being adjustable on saidelevator to cause said spring means to balance said hopper over adifferent range of bodily swing.

11. In the conveyor set forth and defined in claim 10, wherein saidelevator is adjustable as to inclination with the ground, and saidadjustable pivotal connection of the link means with said elevatorprovides a different moment pattern for the hopper in respect to eachdiflerent inclination of the elevator, the addition of automaticcooperative means to inform an operator as to where the pivotalconnection of the link means is to be made with the elevator to balancethe hopper for that specific inclination of the elevator.

12. A conveyor comprising an elevator, a hopper, and

pivotal means to mount said hopper on the elevator for swinging movementbetween a stored inoperative position and a lowered ground contactingoperative position, resilient means connected at one end with saidhopper to balance the same, and operative shiftable mechanism to receivethe other end of said resilient means, said shiftable mechanism beingconnected with said hopper and being responsive to the swinging actionof said hopper to change the position of the other attached end of saidresilient means in relation to the pivotal means of said hopper and tovary the resultant moment force of said resilient means on said hopperin a predetermined relation to the torque force of said hopper duringits movement about said pivotal means.

13. A conveyor as in claim 12, wherein said resilient means are springmembers, said operative mechanism comprise toggle links having one endthereof pivotally mounted in a fixed location on said elevator, theother of said links being connected with a hopper part, said hopper partbeing adapted to actuate the toggle links in a predetermined relation tovary the moment force of the spring members on said hopper in apredetermined value with respect to the torque force exerted by saidhopper in its motion about its pivotal mounting means.

14. A conveyor as in claim 13, wherein said hopper part is a crankelement having a crank pin connection with the other of said links, saidcrank member being freely fulcrumed upon the pivotal means mounting thehopper on the elevator.

15. In the combination of claim 14 wherein said crank element provides abearing unit for the hopper to freely and swingably support said hopperupon said pivotal means of the elevator.

16. In an apparatus, in combination, cooperative connected mechanismscomprising a first stationary section, a second swingable section, ashaft on said stationary section to pivotally support said secondswingable section for arcuate displacement between an operative extendedposition ahead of said stationary section and an inoperative storedposition overlying said stationary section, and counterbalancingstructure coacting between said relatively movable sections to react tothe weight resistance of said swingable second section during thearcuate transposition of said second section between its operative andstored positions, said counterbalancing structure comprising a shiftableguided link, a spring connected at a given point with said link andconnected with said second section at a point remote from the axis ofthe pivotal supporting shaft on said first section, a rotary devicehaving connection with said second section and having a pin thereonmovable in a predetermined path about the axis of said shaft connectingsaid sections, said shiftable guided link being connected with said pinof said rotary device whereby arcuate displacement of said secondsection causes said link to move the point of connection of said springwith said link into different radial distances with respect to the axisof swing of said second section to establish a variable etiective momentarm for said spring and to automatically balance the second section atthe various respective positions of swing assumed thereby.

17. In the combination of claim 16, with the addition of an auxiliaryswingable link interposed between the spring and said given connectingpoint on said shiftable guided link, said auxiliary link and said guidedlink having cooperative stop means thereon to lock said links togetherwhen said second section moves beyond a given angular position in itsarcuate travel to further change the effective spring pull on saidsecond section beyond said angular locking position.

18. A conveyor comprising an elevator, a hopper and pivotal bearingstructure to mount said hopper on said elevator for swinging movementbetween a stored inoperative position and a lowered operative groundengaging position, said pivotal bearing structure comprising a conveyorchain shaft, bearings for said shaft, and mounting units to attach saidbearings to said hopper, said elevator providing apertured platesadjacent opposite sides of said hopper with said mounting units eachjournaled in the plate apertures and providing a rotary disc memberoutwardly beyond the outer side of the adjacent plate, andcounterbalancing means for said hopper each providing mechanismassociated with one bearing means and with one of the elevator platesand comprising a shiftable lever, a pin on said disc member pivotallyconnected with said lever, cooperative guide means carried on said plateand coacting with said lever to guide the free end thereof in apredetermined path when said disc member is rotated by the motion ofsaid hopper, and a spring connected between the free end of said leverand a remote point on said hopper to counterbalance said hopper, theresultant active force of said counterbalancing means on said hopperbeing varied according to the angular position assumed by the hopperthrough the change of the position of the spring connection by themotion of said lever in relation to the pivotal axis of the elevatorshaft with said force being directly responsive to the position of thelever as determined by the pin on the hopper rotated disc member.

19. In the combination of claim 18, wherein said elevator includes meansto adjust the inclination thereof in relation to the ground level, andone of said guide means comprises a link pivotally connected with saidlever and having its other free end attached for pivotal movement on theadjacent side plate, said plate and said free end of said link havingselective attachment means whereby to change the attached location ofsaid link on said plate to compensate for the variation of the elevatorinclination in guiding said lever to attain the proper counterbalancingforce to balance the hopper for the specific inclination of saidelevator.

20. A counterbalancing a aratus for a conveyor having a tilting hopperchute pivotally connected to a conveyor chute so as to be swung bodilyabout a given axis between operative and inoperative positions inrelation to said conveyor chute, said apparatus comprising linkmechanism on said conveyor chute, and a spring connected between saidhopper chute and said link mechanism, said link mechanism including afirst arm carried by said conveyor chute, and a second arm having oneend pivotally connected to said first arm about an axis radially spacedfrom and above said given axis about which the hopper chute is swingableon the conveyor chute, said second arm having its other end operativelyconnected to said hopper chute whereby said link mechanism is actuatedin response to the tilting motion o said hopper chute, said linkmechanism being constructed and arranged to regulate the efiective lineof pull 0 the spring in relation to said given axis to balance thehopper chute as it assumes difierent angular positions with respect tothe conveyor chute.

21. A counterbalancing assembly for a conveyor having a conveyor chuteand a hopper chute pivotally connected to one end thereof so as to beswingable about a horizontal axis into difierent angular positions withrespect to the conveyor chute, said apparatus comprising an articulatelinkage embodying at least two pivotally connected arms, one said armbeing connected to the conveyor chute and the other arm beingoperatively connected to the hopper chute at spaced apart locationsremote from said horizontal axis about which the hopper chute isswingable, said linkage being actuated in response to swing of thehopper chute, and resilient means connected between one said arm of thearticulate linkage and the hopper chute such that the articulate linkageeffectively changes the eficctive line of pull of the coil spring inrelation to said horizontal axis in order to balance the hopper chute asit assumes different angular positions with respect to the conveyorchute about said horizontal axis.

22. A counterbalancing apparatus for a tilting hopper on a conveyorcomprising, in combination, a hopper chute, a conveyor chute, saidhopper chute being pivotally connected to said conveyor chute so as tobe swung bodily between operative and inoperative positions in relationto said conveyor chute about a given horizontal axis, and link mechanismincluding a first arm mounted on the conveyor chute, a second armpivotally connected to said first arm about an axis spaced from saidgiven axis about which the hopper chute is swingable, said second armbeing operatively connected to said hopper chute, and spring meansconnected between the hopper chute and a part of said link mechanismspaced from the pivotal connection of said two arms, said link mechanismbeing constructed and arranged to regulate the effective lirie of pullof the spring in relation to said given axis to balance the hopper chuteas it assumes diflerent angular positions with respect to the conveyorchute.

23, In a conveyor having a hopper mounted at one end thereof so as to bebodily swingable about a given axis on said conveyor, between aninoperative and operative position, an articulated link mechanismmounted on said conveyor end including a portion supported above saidgiven axis, a spring having one end connected to said portion at a pointremote from said given axis and having its other end connected to thehopper to balance the same, said link mechanism being operativelyconnected to the hopper to vary the resultant moment force of the springon said hopper during its swing about said given axis, said portion ofthe linkage mechanism further including means which cfiectively increasethe spacing of its spring connection from the said given axis aboutwhich the hopper tilts as it reaches a predetermined upright positionand is moved past said upright position into its said inoperativeposition.

24. In combination, in a conveyor, an elevator, a hopper for saidelevator, pivotal means on said elevator which supports said hopper fortilting between operative and inoperative positions, andcounterbalancing mechanism for said hopper comprising a spring connectedbetween an outboard portion of the hopper and a vertically extendingfirst member of an articulate linkage, said linkage including a secondmember pivotally connected to the first member below its connection withthe spring, one of said members being connected to the elevator and theother to the hopper by means located to opposite sides of said pivotalmeans in the operative positions of the hopper, said articulate linkagebeing adapted to change the effective line of pull of said spring meansin relation to the axis of swing of said hopper in a manner to keep saidhopper in balance with said spring means, said elevator including meansto adjust the inclination of said elevator in relation to the ground,such adjustment acting to change the limit of the angular swing of saidhopper in relation to the elevator, and said means connecting one ofsaid members of the articulate linkage to the elevator embodyingmultiple attachment means to selectively receive said one member of thearticulate linkage in diflerent positions, said attachment meansestablishing a range of connections that each serve to adjust theoperation of said linkage for counterbalancing the hopper in accordancewith the particular inclination of said elevator.

25. A counterbalancing assembly for a conveyor having a conveyor chuteand a hopper chute pivotally connected to one end thereof so as to beswingable about a horizontal axis into diflerent angular positions withrespect to the conveyor chute, said apparatus comprising a coil springhaving one end connected to a portion of the hopper chute remote fromsaid horizontal axis, and its other end connected to the upper end of afirst of two pivotally connected arms, one said arm being connected tothe conveyor chute and the other arm being connected to the hopper chuteat spaced apart locations, the pivotal connection of said two arms beingdisposed above said horizontal axis about which the hopper chute isswingable and below the connection of the coil spring to the first arm,said arms effectively changing the spacing of the end of the coil springconnected to the hopper chute from the horizontal axis about which thehopper chute is swingable so as to regulate the effective line of pullof the coil spring in order to balance the hopper chute as it assumesdiflerent angular positions with respect to the conveyor chute and aboutsaid horizontal axis.

References Cited by the Examiner 5/92 Grube 198113 3/14 Zimmerman198-114 SAMUEL F. COLEMAN, Primary Examiner.

WILLIAM B. LA BORDE, Examiner.

